Examples of prior art planetary gear drive arrangements are illustrated in the Powischill et al. U.S. Pat. No. 2,902,888, issued Sept. 8, 1959; the Sharpe U.S. Pat. No. 2,343,333, issued Mar. 7, 1944; and the Briones U.S. Pat. No. 1,009,954, issued Nov. 28, 1911.
Attention is also directed to the Hardingham U.S. Pat. No. 593,652, issued Nov. 16, 1897; the Marr U.S. Pat. No. 765,498, issued July 19, 1904; and the McNamara U.S. Pat. No. 742,721, issued Oct. 27, 1903.